1. Field of the Invention
Aspects of the present invention relate to a reduced backlash joint, and a method of making same.
2. Background of the Related Art
Mechanisms for transmitting mechanical force, particularly those transmitting force around corners and bends, often employ joints, fittings or matings. One example such joint in the related art is that used in drive chains for remote actuation of components. In this example, such joints and chains are needed in surgical environments to permit work to be performed in difficult-to-reach areas, such as may occur during abdominal surgery. It is of general interest to ensure that such joints or fittings fit as closely as possible for certain applications.
One problem that can occur with such drive chains when certain fit is not close is called “backlash.” Backlash between connecting joint components, for example links in a chain, can occur when the joint or chain is pushed or pulled for mechanical actuation, or generally when a mechanical component is actuated, for example in rotary or linear motion, or in the case of a universal joint in complex multi-axis motion.
In particular, fitting issues or “give” between joint components or links/connection components such as might be used, for example, in an actuating chain, can cause such backlash when the joint components or links/connection components are used to transmit force. For example, in a surgical use, backlash in the push or pull of a joint components or links/connection components in an actuating chain that controls end effectors or tools in a remotely actuated surgical device during surgery may cause imprecise movements, resulting in over- or under-compensation or other imprecise activating motions on the part of the user. Such over- or under-compensation, or other imprecise activating motion, may lead to accidents or sloppiness in a remotely-actuated surgical procedure. Moreover, “give” in the joint or chain makes its motion less intuitive for the user and, therefore, less easily and precisely controlled, making precision work more difficult.
Although precision machining of components of such chains can, in some cases, improve precision actuation, such machining is often expensive and difficult. It can be especially difficult to machine, with precision, mating surfaces on chain links that are often responsible for the “give” or backlash effect described above.
Therefore, improvements in joint components or links/connection components and general mechanisms are desired.